Constant Direction Four Quadrant Lift Type Vertical Shaft Wind Power Generator

ABSTRACT

A constant direction four quadrant lift type vertical shaft wind power generator is provided, which includes a truss-type wind wheel formed by an upper wind disc ( 5 ), a lower wind disc ( 3 ), and supporting rods ( 11 ); a speeder ( 8 ); and a generator ( 9 ), in which the wind wheel and the speeder ( 8 ) are sleeved on a central shaft ( 2 ), several groups of vanes ( 7 ) are perpendicularly arranged at a diametral top end of the wind wheel by their respective pivots ( 10 ), the wind wheel and the vanes ( 7 ) are disposed at an upper end of the equipment, and the generator ( 9 ), the speeder ( 8 ), and a controller are disposed at a bottom of the equipment. The wind power generator can be conveniently installed, operated, and maintained.

BACKGROUND OF THE INVENTION

1. Field of Invention

The present invention relates to a vertical-shaft wind power generatorin a new energy field, and more particularly to a constant directionfour quadrant lift type vertical shaft wind power generator.

2. Related Art

It is well-known that vanes of a vertical-shaft wind power generatorgenerate a driving force at one side of the pivots and inevitablyproduce resistance when they rotate to the other side of the pivotsbased on the aerodynamic principle. Therefore, the power generationefficiency is not very high. For a long time, researchers have beenworking hard at researches about the vane shape, for example, theSavoninc vane enables the power to be greater than the resistance toaccomplish other advantages of the vertical-shaft wind power generator.Currently, hundreds of design patents about the vertical-shaft windpower generator are available. Unfortunately, the power generationefficiency still cannot catch up with the horizontal-shaft wind powergenerator, with the exception of the France Darrieus vertical-shaft windpower generator. But the France Darrieus vertical-shaft wind powergenerator cannot realize self-start and may stop rotating at a smallwind.

SUMMARY OF THE INVENTION

In view of the defects of the current vertical-shaft wind powergenerator, the present invention is directed to a vertical-shaft windpower generator with a high power generation efficiency by making fulluse of the aerodynamic principle in combination with scientificexperiment methods, and the wind power generator is convenient toinstall, operate, and maintain, and has stable and reliable performance.

The objective of the present invention is implemented through thefollowing measures.

A constant direction four quadrant lift type vertical shaft wind powergenerator is provided, which includes a truss-type wind wheel formed byan upper wind disc, a lower wind disc, and supporting rods; a speeder;and a generator, in which the wind wheel and the speeder are sleeved ona central shaft, several groups of vanes are perpendicularly arranged ata diametral top end of the wind wheel by their respective pivots, thewind wheel and the vanes are disposed at an upper end of the equipment,and the generator, the speeder, and a controller are disposed at abottom of the equipment, which can be realized through landinginstallation.

An overall shape of the vanes is an air-foil shape with equal crosssections, and a height of the vanes is equivalent to that of the windwheel. A shape of the cross section is that, a circular-arc radius of ahead portion is 1/18- 1/22 of a vane chord length, an arc radius of anouter surface is ⅜ of the chord length, an arc radius of an innersurface is 3/16 of the chord length, a central angle of an overallcircular-arc portion is 40-50 degrees, an arch height of a circular arcof the outer surface is ⅕- 1/7 of the chord length, and an arch heightof a circle chord of the inner surface is 1/10- 1/14 of the chordlength; a back portion of each of the vanes is linear intersectionbetween the outer surface and the inner surface; and the pivots of thevanes are located at positions 1/7-⅙ of the chord length from the headportion.

A number of the vanes is three or an integral multiple of three, thewind wheel is of a corresponding regular polygon structure, and each ofthe vanes is perpendicularly arranged at a corresponding vertex angleposition of the wind wheel. The vanes are of a hollow structure with aframework braced therein. An arc-shaped wind collecting baffle isdisposed at an upwind side of the wind wheel to increase the wind forcevolume of the vanes and increase the output power. The vanes are made oflight, weather-resistant, and corrosion-resistant materials.

A stop mechanism is disposed at a top and/or bottom portion of thepivots of the vanes, and the top and/or bottom portion of the pivots iscorrespondingly sleeved with a disc having a fan-shaped notch fittingwith the pivots, a central angle of the notch is 65-75 degrees, and thestop mechanism is axially or radially arranged to fit with thefan-shaped notch, so as to control a maximum angle of attack to be 25-30degrees when the vanes are in an upwind direction and a maximum angle ofattack to be 40-45 degrees when the vanes are in a downwind direction.As a result, the vanes are changed at this position. Under the effect ofthe wind power, four quadrants are all corresponding to the lift forcedue to the aerodynamic principle.

The stop mechanism is a mechanical type or electrical type, and performsa stopping operation on the vanes by being inserted into and withdrawnout of the fan-shaped notch through a sliding rod. The mechanical-typestop mechanism includes a stop assembly and a sliding rod. A guidingwheel is disposed at two sides of the sliding rod, a front end isconnected with a sliding wheel, and a back end is connected with awindward baffle at the upper portion of the wind wheel through steelwires. The electrical-type stop mechanism includes an anemometer and amotor mechanism.

When encountering a strong wind, the windward baffle or anemometerenables the sliding rod to withdraw out of the fan-shaped notch underthe electrical or mechanical driving motion, and the vanes automaticallyrotate downwind to reach positions where the wind force is at theminimum level, so as to avoid being damaged, and then the vanes areautomatically restored after the strong wind. In order to enhance thewind-resistant capability of the entire generator, medium andlarge-scaled units are fixed by adding inclined steel wire cables at atop end thereof. In order to increase the power generation capability,the wind wheel can be stacked and expanded in a building block mode.

COMPARED WITH THE PRIOR ART, THE PRESENT INVENTION HAS THE FOLLOWINGADVANTAGES

In the wind power generator structure developed by making use of theaerodynamic principle in combination with scientific experimentsaccording to the present invention, during the rotation of the windwheel, the vanes are always maintained at a state of generating liftforce, and the tangential component force thereof drives the wind wheelto continuously rotate towards a constant direction.

The power generation efficiency of the present invention is higher thanthat of the commonly used horizontal-shaft wind power generator, withoutusing a windward mechanism or hoisting an engine room weighing up totens of tons and including a generator and a speeding gear case thereinto a tower top of tens of meters. In addition, the controller,generator, and speeder are very simple and are not restrained by theweight. The vane does not need to support its own weight, but only actsupon the wind power to push the wind wheel, which is not of a cantileverstructure and is made portable. Meanwhile, the technical requirements onthe controller, vanes, and metal framework are reduced, therebyresulting in the decreased manufacturing cost and conveniences ininstallation, operation, and maintenance, and making full use of theadvantages of the vertical-shaft wind power generator and promoting thedevelopment of the wind power generator industry.

In addition, the present invention further includes a flexible strongwind cutout protection mechanism. The vanes are arranged downwind whenthe wind is strong, and the force impinged on the vanes is reduced tothe minimum level, and then the vanes are automatically restored afterthe strong wind. This is essential for the safety and reliability of thewind power generator.

The engine room of the present invention is implemented through landinginstallation, which greatly improves the stability, reliability, andinstallation, operation, and maintenance performances, and reduces therequirements on the units and framework intensity. The wind wheel can bestacked in a building block mode, so as to increase the power and beconvenient for the standardization of the assembly.

The overall cost of the present invention can be reduced below 70% ofthe commonly used horizontal-shaft wind power generator. Besides, thewind power generator of the present invention is more stable andreliable, which is expected to reduce the online electricity price ofthe wind power generation to a level close to that of the coal powergeneration, thereby greatly promoting the development of the wind powerindustry, speeding up the construction of the wind power fields, savingenergy and reducing exhaustion, and producing far-reaching impacts onimproving the economic and social benefits.

The cross sections of the vanes are not changed along the whole length,which conforms to the Bernoulli's theorem, i.e., when the wind blows thevanes, the lift force is generated. The shape of the cross sections ofthe vanes used in the present invention is also decided throughaerodynamic experiments, and the shape of the cross sections of thevanes is combined with the wind wheel structure to achieve higher powergeneration efficiency.

In order to overcome the problem about the poor power generationefficiency of the existing vertical-shaft wind power generator, thepresent invention provides a constant direction four quadrant lift typevertical shaft wind power generator. Furthermore, according to thenational standard, a power output characteristic test of a wind powergenerator in a wind tunnel is carried out in the state authorizedlaboratory named China Ship Scientific Research Center of the ChinaShipbuilding Industry Corporation (CSIC), and the specific test contentscan be obtained with reference to Appendix 1 China's National DefenseScientific and Technical Report. The experiment is based on the nationalstandard Off-Grid Wind Turbine Generator Systems—Part 3: Wind TunnelTest Methods (GB/T19068.3-2003). The test samples include a ZXVWG windpower generator (two models, i.e., 200 W and 300 W) developed accordingto the present invention and a traditional triple-vane horizontal-shaftpower generator with a model of FD-400 (400 W), and the test contentsinclude two aspects, i.e., startup wind speed and power outputcharacteristics.

The report provides the test results of the above wind power generatorsin the wind tunnel, analyzes the test structures, and compares the poweroutputs at a wind speed of 12 m/s. As seen from the test, in terms ofthe startup wind speed, ZXVWG is 2.8 m/s and FD-400 is 3.3 m/s. At awind speed of 12 m/s, ZXVWG-200 wind power generator can obtain theoutput power equal to that of the FD-400 traditional wind powergenerator, although the swept area of the former is about 26% less thanthat of the latter. ZXVWG-300 wind power generator outputs a power up to187.4 W at the wind speed of 12 m/s, which is about 26% greater thanthat of the FD-400 traditional wind power generator. The outputcharacteristic curves of the three types of wind power generators canalso be obtained with reference to FIG. 5, and it can be expected fromthe curve tendency that, with the increase of the wind speed, ZXVWG-300wind power generator is likely to generate greater output power. Pleaserefer to Table 1 for the comparison results.

TABLE 1 Comparison table for test results at a wind speed of 12 m/sOutput Power of Generator Generators at Rated Power Swept Area WindSpeed of Generator Model (W) (m²) 12 m/s ZXVWG-300 300 1.68 187.4ZXVWG-200 200 1.68 148.6 FD-400 400 2.27 148.8

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural view of a wind power generator.

FIG. 2 is a diagram illustrating working principle of a wind powergenerator.

FIG. 3 is a schematic structural view of a vane.

FIG. 4 is a schematic structural view of a stop mechanism.

FIG. 5 is a comparison graph of power output characteristic curves ofthree types of wind power generators.

In the above drawings: 1. Support, 2. Central shaft, 3. Lower wind disc,4. Strut, 5. Upper wind disc, 6. Strong wind cutout protection device,7. Vane, 7-1. First vane, 7-2. Second vane, 7-3. Third vane, 7-4. Fourthvane, 7-5. Fifth vane, 7-6. Sixth vane, 8. Speeder, 9. Generator, 10.Pivot, 11. Supporting rod, 12. Stop assembly, 13. Sliding wheel at topend, 14. Sliding rod, 15. Sliding wheel, 16. Disc, R1. Circular-arcradius of head portion, R2. Circular-arc radius of inner surface, R3.Circular-arc radius of outer surface, L. Chord length, h1. Arch heightof external arc, h2. Arch height of internal arc, α₁. Angle of attack inupwind direction, α₂. Angle of attack in downwind direction, β.Fan-shaped notch, and γ. Central angle of circular-arc portion.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is further described below with reference to theaccompanying drawings.

As shown in FIG. 1, the bottom portion of the wind power generator ofthe present invention is a support, and at a middle height position ofthe support 1, a platform with a generator and a speeder installedthereon is configured. A central shaft 2 is arranged in the center ofthe support. A wind wheel is sleeved on the central shaft, in which aradial thrust bearing is installed on the lower end thereof and ajournal bearing is installed on the top end thereof to ensure that thewind wheel can flexibly rotate while being sleeved on the central shaft2. A generator 9, a speeder 8, and a controller can also be implementedthrough landing installation. When rotating, the wind wheel drives thespeeder 8 at the lower end to rotate and then drives the generator 9 togenerate power. The positions of vanes 7 where the vanes change theirlocations among different quadrants under the effect of the wind powerare restrained by a stop mechanism. A baffle or anemometer of a strongwind cutout protection device 6 is disposed at the top portion. When thewind power exceeds a predetermined value, the baffle falls down, thestop mechanism is withdrawn, and the vanes 7 automatically orientatewindward in the strong wind, and the force impinged on the vanes 7 areturned to a minimum state, so as to protect the vanes 7 from beingdamaged.

As shown in FIG. 2, the number of the vanes 7 in the wind powergenerator of the present invention is selected to be 6, that is, a firstvane 7-1, a second vane 7-2, a third vane 7-3, a fourth vane 7-4, afifth vane 7-5, and a sixth vane 7-6 respectively. An upper wind disc 5and a lower wind disc 3 are both of a regular polygon structure and theupper and lower wind discs and supporting rods 11 constitute atruss-type wind wheel. Each of the vanes 7 is perpendicularly arrangedat a corresponding vertex angle position of the upper and lower winddiscs. Pivots 10 of the vanes are all installed with bearings.

As shown in FIG. 3, an overall shape of the vanes 7 of the presentinvention is an air-foil shape and of a hollow structure with aframework braced therein. The vanes 7 are designed with equal crosssections and the height of the vanes is equivalent to that of the windwheel. The shape of the cross section is specifically that, acircular-arc radius of a head portion R1 is 1/18- 1/22 of a vane chordlength L, an arc radius of an outer surface R3 is ⅜ of the chord lengthL, an arc radius of an inner surface R2 is 3/16 of the chord length; acentral angle γ of an overall circular-arc portion is 40-50 degrees, anarch height of a circular arc of the outer surface (i.e., an outer archheight h1) is ⅕- 1/7 of the chord length, an arch height of a circlechord of the inner surface (i.e., an inner arch height h2) is 1/10- 1/14of the chord length, a back portion of each of the vanes is linearintersection between the outer surface and the inner surface, and thepivots 10 of the vanes are located at positions 1/7-⅙ of the chordlength from the head. The vanes 7 are made of light, weather-resistant,and corrosion-resistant materials, so that the requirement for themechanical intensity of the materials of the vanes 7 is rather low.

The present invention may further add an arc-shaped wind collectingbaffle in an upwind direction of the wind wheel, so as to collect theincoming winds, increase the force impinged on the vanes, and increasethe output power.

As shown in FIG. 4, a stop mechanism is disposed at a bottom portion ofthe pivots 10 of the vanes, and the bottom portion of the pivots 10 iscorrespondingly sleeved with a disc 16 having a fan-shaped notch βfitting with the pivots. A central angle of the notch is 65-75 degrees,and the stop mechanism is axially or radially arranged to fit with thefan-shaped notch β, so as to control a maximum angle of attack to be25-30 degrees when the vanes 7 are in an upwind direction and a maximumangle of attack to be 40-45 degrees when the vanes 7 are in a downwinddirection. As shown in FIG. 4, a mechanical-type stop mechanism includesa stop assembly 12 and a sliding rod 14. A guiding wheel 13 is disposedat a top end of two sides of the sliding rod 14, a front end isconnected with a sliding wheel 15, and a back end is connected with awindward baffle at the upper portion of the wind wheel through steelwires. In a normal situation, the sliding rod 14 is inserted into thenotch of the disc 16 and performs a stopping operation on a rotatingangle of the vanes. When encountering a strong wind, the windward baffledrives the sliding rod 14 to be withdrawn out of the notch, and thevanes 7 automatically rotate downwind to reach a position where the windforce is at the minimum level, so as to avoid being damaged, and thenthe vanes 7 are restored automatically after the strong wind. The vanes7 of the present invention are changed at the illustrated positions.Under the effect of the wind power, four quadrants are all correspondingto the lift force due to the aerodynamic principle.

The stop mechanism may be disposed at a top portion of the pivots 10 ofthe vanes, and may also be disposed at the top or bottom portion of thepivots at the same time.

In additional to the above mechanical-type structure, the stop mechanismmay further adopt an electrical-type structure. The electrical-type stopmechanism automatically detects and controls the sliding rod to bewithdrawn out of and inserted into the fan-shaped notch of the pivots ofthe vanes through an anemometer and a motor mechanism, so as to controlthe angle of attack of the vanes. When encountering a strong wind, theanemometer enables the sliding rod 14 to be withdrawn out of the notchunder an electrical driving motion, and the vanes 7 automatically rotatedownwind to reach a position where the wind force is at the minimumlevel, so as to avoid being damaged, and then the vanes 7 areautomatically restored after the strong wind.

In order to increase the power generation capability, the wind wheel canbe stacked and expanded in a building block mode. In order to enhancethe wind-resistant capability of the entire generator, medium andlarge-scaled units are fixed by adding inclined steel wire cables at atop end thereof.

The number of the vanes in the wind power generator of the presentinvention may be selected as three or an integral multiple of three, theupper and lower wind discs of the wind wheel can adopt a correspondingregular polygon structure, and each of the vanes is perpendicularlyarranged at a corresponding vertex angle position of the wind wheel.

As shown in FIG. 5, ZXVWG-300 denotes an output characteristic curve ofa 300 W generator designed according to the present invention, ZXVWG-200denotes an output characteristic curve of a 200 W generator designedaccording to the present invention, and FD-400 denotes an outputcharacteristic curve of a 400 W traditional horizontal shaft wind powergenerator. Upon the comparison test with the traditional wind powergenerator, the swept area of the generator according to the presentinvention is 26% less than that of the horizontal-shaft generator. In asituation that the capacity of the generator is 25% less than that ofthe traditional generator, at a wind speed of 12 m/s, the generationpower of the wind power generator designed according to the presentinvention is about 26% higher than that of the traditional wind powergenerator, and has a rising tendency along the curve of the cube of thewind speed.

1. A constant direction four quadrant lift type vertical shaft wind power generator, comprising: a truss-type wind wheel, formed by an upper wind disc, a lower wind disc, and supporting rods; a speeder; and a generator, wherein the wind wheel and the speeder are sleeved on a central shaft, several groups of vanes are perpendicularly arranged at a diametral top end of the wind wheel by respective pivots thereof, the wind wheel and the vanes are disposed at an upper end of the equipment, and the generator, the speeder, and a controller are disposed at a bottom of the equipment.
 2. The wind power generator according to claim 1, wherein a number of the vanes is three or an integral multiple of three, the wind wheel is of a corresponding regular polygon structure, and each of the vanes is perpendicularly arranged at a corresponding vertex angle position of the wind wheel.
 3. The wind power generator according to claim 2, wherein an overall shape of the vanes is an air-foil shape with equal cross sections; a height of the vanes is equivalent to that of the wind wheel; and a shape of the cross section is that a circular-arc radius of a head portion is 1/18- 1/22 of a vane chord length, an arc radius of an outer surface is ⅜ of the chord length, an arc radius of an inner surface is 3/16 of the chord length, a central angle of an overall circular-arc portion is 40-50 degrees, an arch height of a circular arc of the outer surface is ⅕- 1/7 of the chord length, and an arch height of a circle chord of the inner surface is 1/10- 1/14 of the chord length; a back portion of each of the vanes is linear intersection between the outer surface and the inner surface; and the pivots of the vanes are located at positions 1/7-⅙ of the chord length from the head portion.
 4. The wind power generator according to claim 3, wherein the vanes are of a hollow structure with a framework braced therein, and the vanes are made of light, weather-resistant, and corrosion-resistant materials.
 5. The wind power generator according to claim 3, wherein an arc-shaped wind collecting baffle is disposed at an upwind side of the wind wheel.
 6. The wind power generator according to claim 3, further comprising: a strong wind cutout protection mechanism, wherein the mechanism is formed by a windward baffle or anemometer and a stop mechanism of the vanes, and medium and large-scaled units are fixed by adding inclined steel wire cables at a top end thereof.
 7. The wind power generator according to claim 3, wherein a stop mechanism is disposed at a top and/or bottom portion of the pivots of the vanes, and the top and/or bottom portion of the pivots is correspondingly sleeved with a disc having a fan-shaped notch fitting with the pivots, a central angle of the notch is 65-75 degrees, and the stop mechanism is axially or radially arranged to fit with the fan-shaped notch, so as to control a maximum angle of attack to be 25-30 degrees when the vanes are in an upwind direction and a maximum angle of attack to be 40-45 degrees when the vanes are in a downwind direction.
 8. The wind power generator according to claim 7, wherein the stop mechanism is a mechanical type or electrical type, and performs a stopping operation on the vanes by being inserted into and withdrawn out of the fan-shaped notch.
 9. The wind power generator according to claim 8, wherein the mechanical-type stop mechanism comprises a stop assembly and a sliding rod, a guiding wheel is disposed at a top end of two sides of the sliding rod, a front end is connected with a sliding wheel, and a back end is connected with a windward baffle at the upper portion of the wind wheel through steel wires; and the electrical-type stop mechanism comprises an anemometer and a motor mechanism.
 10. The wind power generator according to claim 1, wherein the wind wheel is stacked and expanded in a building block mode. 